Re: [PATCH v3 0/4] git-p4: Improve branch support
- From
- Pete Wyckoff <pw@padd.com>
- Date
- Aug 20, 2011, 19:14 UTC
- Message-ID
- <20110820191407.GD7135@arf.padd.com>
- In-Reply-To
- <CAOpHH-WeLWyEZaktYRzVN+dfgqu3==o4bgrfzpvS-QUCQboPgg@mail.gmail.com>
vitor.hda@gmail.com wrote on Fri, 19 Aug 2011 15:30 +0100:
Show 49 quoted lines
> On Fri, Aug 19, 2011 at 12:53 PM, Pete Wyckoff <pw@padd.com> wrote: > > Patches 1 and 2 are great. We should have gotten those in way > > back when you first submitted them. I happily ack those. > > > > I'm still a bit hung up on #3, mainly because I don't get branch > > support. Let me play around with your test. Having this > > playbook of how it is supposed to work will help to educate me. > > (I am probably going in too much detail here. Please skip any > redundant information.) > > In general, you can see branches in P4 as you do in SVN. They are > simple copies from one directory to another. For example: > > p4 integrate //depot/big/directory/path/myproj/version_A \ > //depot/big/directory/path/myproj/version_B > > Now the history of "version_B" is tied to "version_A". If you want to > integrate (merge, in this case) new updates from one of the > directories to the other you can just rerun the above command > (version_A and version_B order may change depending on the direction > of the merge). > > P4 also allows you to define "branch specs" that you can use as a > short hand instead of having to type in the full directory paths. So, > assuming that you have a branch named "myproj_B" with the following > view defined: > > //depot/big/directory/path/myproj/version_A \ > //depot/big/directory/path/myproj/version_B > > When you want to integrate it again you can simply type: > > p4 integrate -b myproj_B > > or, if you want to integrate from version_B into version_A instead: > > p4 integrate -b myproj_B -r > > git-p4 is using these branch specs to identify branches. Without this > extra information it is nearly impossible for it to identify branches > because an integrate can be done of a single file. > > But since P4 does not strictly require branch specs and because most > of the time integrations are done through P4V, then most of the time > no branch specs are created. Now, if this happens git-p4 will not be > able to detect branches! And creating branches in P4 just for git-p4 > does not make much sense, right? This is the main reason behind the > third patch... :)
Thank you for these useful comments. I have taken a first stab at documenting the bevy of confusing branch flags and settings in git-p4. Please correct my errors and add other information that is missing.
In particular, a clear case of how to set up the branches for the branchList example would be good. My minimal test did not exactly work.
-- Pete
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From 36608a6e195041e8738bab24b84fadd0bf386865 Mon Sep 17 00:00:00 2001 From: Pete Wyckoff <pw@padd.com> Date: Sat, 20 Aug 2011 15:04:09 -0400 Subject: [PATCH 4/4] git-p4: branch detection documentation start
Initial stab at documentation for --detect-branches and the new branchList config setting.
Signed-off-by: Pete Wyckoff <pw@padd.com> --- contrib/fast-import/git-p4.txt | 48 +++++++++++++++++++++++++++++++++++++++- 1 files changed, 47 insertions(+), 1 deletions(-)
diff --git a/contrib/fast-import/git-p4.txt b/contrib/fast-import/git-p4.txt index 52003ae..6d21557 100644 --- a/contrib/fast-import/git-p4.txt +++ b/contrib/fast-import/git-p4.txt @@ -265,11 +265,57 @@ Only use branch specifications defined by the selected username. git-p4.branchList -List of branches to be imported when branch detection is enabled. +List of branches to be imported when branch detection is enabled. This +example shows that branchA and branchB are both created off branch main. git config [--global] git-p4.branchList main:branchA git config [--global] --add git-p4.branchList main:branchB +Branch Detection +================ + +There are a few options that try to automatically create branches in git +corresponding to branches in p4. + +Unfortunately, the concept of branch in p4 is quite different: a p4 +branch is a mapping from one area of the repository to another. It is +used as input to "p4 integrate" to specify the source and destination of +an integration. + +If you have a repository where all the branches are below a single +directory, you can use "--detect-branches" when cloning or syncing to +have git-p4 automatically look up the p4 branches and use these to +generate branches in git. Example: + + P4 repository structure: + + //depot/main/... + //depot/branch1/... + + View section from "p4 branch -o branch1" + + //depot/main/... //depot/branch1/... + + Git clone command: + + git-p4 clone --detect-branches //depot@all + + Produces a separate branch in remotes/p4 for + //depot/main (called "master"), and one for //depot/branch1 + (called "depot/branch1"). + +However, it is not necessary to create branches in p4 to be able to +use them like branches. It is quite difficult to detect this +automatically, but a git configuration setting "git-p4.branchList" can be +used to explicitly identify branch relationships. It is a list of +"source":"destination" pairs, like a simple p4 branch specification, +where the "source" and "destination" are the path elements in the +p4 repository. The example above relied on the presence of the p4 +branch. Without that, you can get the same results by setting: + + git config git-p4.branchList main:branch1 + + Implementation Details... =========================
-- 1.7.5.4